The present invention relates to a refrigerated showcase, and more particularly to a refrigerated showcase of energy saving type that is favorably used in a supermarket or the like.
Heretofore, a refrigerated showcase in which a cold air flow is circulated along its bottom wall, rear wall and top wall and across its front opening to refrigerate the interior of the showcase, and preferably another cool air flow is circulated outside of and along the circulating route of the cold air flow to prevent the cold air flow from being warmed up, has been known.
In the case where the above-mentioned type of refrigerated showcase is used in a supermarket or other shops for displaying and storing fresh goods or the like, however, after the shop has closed at night, if the refrigerator of the refrigerated showcase is operated at the same condition as the operation during the business hours when the access to the interior of the showcase is necessary, then an unnecessary electric power will be consumed by the refrigerator. On the contrary, if the refrigerator is stopped in operation or is reset at a higher regulation point of temperature, then because of inflow of a warm ambient air into the showcase through the front opening, the temperature at the interior of the showcase would be raised up to an undesirable level. Therefore, it will be conceived to cover the front opening of the refrigerated showcase with a curtain after the shop has closed, for the purpose of protecting the goods within the showcase from being damaged and preventing the warm ambient air from entering the showcase, to avoid temperature rise at the interior of the showcase even when the refrigerating capability of the refrigerator is weakened.
However, if the curtain covering the front opening of the showcase is a single layer of curtain, a moisture in the atmospheric air will dew on the outside surface of the curtain contacting the atmospheric air because of an extremely large temperature difference between the inside and outside surfaces of the curtain, and hence waterdrops will fall along the curtain, resulting in contamination of a passageway in front of the showcase or goods accommodated in the front portion of the showcase. If the curtain is made of a gas-permeable material in order to prevent such dewing on the surface of the curtain, then the atmospheric air will air the refrigerated showcase, resulting in frosting on the compressor or the like in the refrigerator, and this necessitates defrosting operations and thus lowers the refrigerating efficiency.